1. Field of the Invention
The present invention relates to a method and apparatus for efficient conduction cooling of surface-mounted electronics and, in particular, to improvements in such a method and apparatus utilizing heat-conducting compressible button contacts in thermal contact between a heat sink and one or more surface-mounted electronic devices, including those that are not equally distanced from the heat sink.
2. Description of Related Art and Other Considerations
High power (e.g., greater than two watts) surface mounted parts are not generally used in military systems. When used, however, heat energy is conducted through thermal vias underneath each part. Ball-grid-arrays and PQFPs are usually cooled by attaching a large finned heat-sink or aluminum plate to the top of the component. It is difficult to effectively remove heat from these components at extended temperatures encountered in military systems as heat is removed from components from the bottom of the component. Ball grid array parts with exposed bare dies have used a top mounted finned heatsink or plate. Component height variations create one or more thermal gaps in this arrangement, which gaps must be compensated for by utilizing some adjustable mechanism. In one adjustable mechanism, the heatsink plates employ a threaded thermal slug which must be adjusted for each part.
Disadvantages exist in such arrangements, which add time and other costs. Each electronic part requiring a heat sink must be individually adjusted. The heatsink plate must be sufficiently thick to support a threaded slug.